Exchange Database Consistency: The Exchange database consistency check involves inspecting transaction and database log files for errors that might create mounting issues. It detects the problems that prevent users from accessing, modifying, or deleting mailbox emails.
In case the inspection encounters an error, it needs prompt resolution before you back up the database. What will happen if the Exchange database consistency check fails to fix the issues? How can you deal with such instances? What types of repairs can you perform to bring the database to a consistent state? This blog discusses all these points in detail.
How to Perform the Exchange Database Consistency Check?
Users perform the consistency check on the Exchange database files during a Windows Backup operation. To serve this purpose, you must have assigned the requisite mailbox recovery permissions.
The consistency check finds out if the database is in a healthy state and good enough to use for recovery. If the check is a success, the Exchange data is ready for recovery. Just opposite, a failed check finishes the backup with the following warning message:
“The application will not be available for recovery from this backup. The consistency check failed.”
It indicates the unavailability of the data for recovery due to a failed backup.
Notably, the Windows Server Backup carries out a consistency check on the snapshot captured for the backup. This helps to determine the consistency status before copying files from the snapshot to backup media, saving considerable time and effort. It also prevents the user from analyzing the data from different sources.
Reason behind the Exchange database consistency check failure?
The Windows Server Backup operation checks the log files with database information during the consistency check. If the database information matches the log file data, it ensures an updated status.
In case of an inconsistent or mismatched state, the database will show an error concerning backup failure, citing its limitation to create an Exchange server backup. This error can occur due to several factors. Here are a few of them:
- Missing transaction log files
- Compromised EDB files
- Inconsistent or dismounted database
- Bad sectors on the hard drive
- Page-level corruption
- Dirty Shutdown state
- Antivirus interference
- Storage exceeding database size limit
- Trouble with Volume Shadow Copy Service (VSS) writers
Pointing to the last error, the VSS settings are crucial to facilitate consistent backups and data integrity in the Exchange Server database. An error in these settings can cause failures in the consistency check, which necessitates the need for quick resolution.
Resolving the Consistency Check Failed Error
There can be multiple ways to deal with this error and make way for flawless functioning of the Exchange database.
1. Disable the Exchange consistency check
During the Windows Server Backup, you may disable the consistency check in the Exchange Server to avoid the error. However, it will not let you restore the Exchange database from the backup in the future, when needed. This will cause more issues.
2. Use Eseutil
Microsoft’s built-in tool called ESEUTIL can deal with the consistency check issue in the Exchange database. Nevertheless, it can fix only minor issues and is not effective at resolving major issues, such as consistency check failures.
You can run the Eseutil command in the Exchange Management Shell (EMS) environment before starting the WSB operation. It will verify the Exchange database and transaction log for smooth or flawed functioning.
Run the following command to verify the database and log files.
Eseutil /g “D:\program files\exchsrvr\RDBdata\priv01.edb
This command will check the following:
- The logical integrity of the database
- The database is in read-only mode due to an inconsistent status
Here is more information that you can check by using the Eseutil command
- Check the current state of the database: Eseutil /mh <Database name>
- Check the current state of the log files: Eseutil /ml <log file name >
These Eseutil commands can fix minor issues and may not be effective in resolving bigger errors. More likely, you may get the following error if the check fails:
Operation terminated with error -1206 (JET_errDatabaseCorrupted, Non database file or corrupted db) after 0.936 seconds.
Moving on, if you find an error and wish to repair the database to enable it to resume functioning properly, you may use the following command: Eseutil /P <Database name>
This last command is effective, but it can wipe out your sensitive data because of corruption. Therefore, make sure to have a recent backup of your database before opting for it.
These commands do their job with certain limitations. For instance, they take much time, run the risk of data loss, and do not guarantee complete resolution despite deleting the corrupted data. To overcome these restrictions, using professional Exchange recovery software can be a suitable option.
3. Use an Exchange recovery tool
A third-party data recovery application is likely to have an upper hand over the manual methods owing to multiple factors. Here are some of them:
- Advanced algorithms to extract data from corrupted EDB files
- Export the restored data to a PST file
- No fear of data loss during backup failures due to failed consistency check
- Recover dismounted and offline EDB files
- Restore data from large and multiple corrupted EDB files
- Easy to use with a user-friendly interface
- No need for technical knowledge to use these tools
When looking for a professional Exchange recovery tool in the market that abides by these features, you will find Stellar Repair for Exchange as a feasible option.
Recommended: Professional SEO Services
Conclusion
In the Exchange Server database, consistency check refers to the inspection of the database and transaction log files for mounting errors during the Windows Server Backup (WSB) operation. The check finds the errors that prevent the users from gaining access to the mailbox data, modifying, or deleting it.
Often, these checks fail due to several reasons, ranging from missing transaction log files to corrupt EDB files, VSS writers to page-level corruption, and so on.
As a result, you get the error: The application will not be available for recovery from this backup. The consistency check failed. To resolve this error, you can try to disable the consistency check in the Exchange Server database.
This will prevent you from restoring the Exchange database from the backup when required, leading to more trouble. Alternatively, Eseutil commands can also prove effective in this regard. For instance, Eseutil/p can repair the Exchange database with the loss of corrupted data.
Nevertheless, considering data loss, excessive time consumption, and no guarantee of error-free execution of the commands, these manual methods are less effective.
To avert such issues, users prefer confiding in a professional Exchange recovery tool. Software, such as Stellar Repair for Exchange, can be a viable option to efficiently serve this cause.
Tags: DBCC CHECKDB table, DBCC CHECKDB with tableresults, DBCC CHECKTABLE repair_allow_data_loss, SQL error 824 attach database, DBCC CHECKDB master, How to check DBCC CHECKDB progress, CHECKTABLE, and DBCC CHECKDB with DATA_PURITY.